Evaporator



Sept. 13, 1949. c. c. HUBBELL EVAPORATOR 2 Sheets-Sheet 1 Filed April 4, 1944 U/MRL 5 6. Ho an 1.

ATTORNEYS Se t. 13, 1949. c. c. HUBBELL 2,431,511

EVAPORATOR Filed April 4, 1944 2 Sheets-Sheet 2 Patented Sept. 13, 1949 EVAPORATOR The Yoder Company, poration of Ohio Charles C. Hubbell, Meadville, Pa., assignor to Cleveland, Ohio, a corpo- Application April 4, 1944, Serial No. 529,500 8 Claims. (Cl. 62-126) This invention relates to apparatus for refrigeration, particularly of the type where a suitable refrigerant is compressed, liquefied and then fed into evaporator plates where it expands into a gaseous state and is returned to the compressor to repeat the cycle.

In systems of this type one of the difliculties has been the lubricating oil from the compressor will leak into and become mixed with the body of the refrigerant. Where such oil is permitted to accumulate in the evaporator plate, a, serious decrease in efiiciency results. Accordingly, one of the primary objects of this invention is to provide for a housing, cabinet or other enclosure an evaporator plate so constructed that any oil which may be mixed with the refrigerant will be carried off from the evaporator plate and returned to the compressor. A further object of the invention is to provide an evaporator plate so constructed that any oil not carried off during the active portion of the cycle will be trapped in the upper portion of the evaporator plate and not permitted to settle to the bottom thereof, so that it may be readily carried off when the active cycle is resumed.

In the so-called full-flooded type of evaporator plate it frequently occurs that the liquid refrigerant is not entirely asified when it leaves the evaporator plate on its return to the compressor. This not only decreases the efliciency of the unit but causes an undesirable frosting on the return portions of the system. Therefore, a further object of the invention is to provide an evaporator plate so constructed that the gasified refrigerant will be completely dry rather than wet, when it leaves the evaporator plate.

Experience has shown that the efliciency of the evaporator plate is in direct relation to the turbulcnce of the refrigerant. Accordingly, a further object of the invention is to provide an evaporator plate having small passageways relative to the entire area of the plate, and provided with baiiies which will cause greater turbulence of the refrigerant not only-to increase the efficiency, but to insure the carrying back to the compressor any oil which may be entrained with the refrigerant.

For quantity production it is desirable to have an evaporator plate of a single design which may be applied to various installations, either in a vertical or horizontal position. Accordingly, a further object of the invention is to provide an evaporator plate so constructed that it may be bent to any desired contour and used in either a vertical or horizontal position.

The invention consists of the construction, com- 2 bination and arrangement of parts as herein illustrated, described and claimed.

In the accompanying drawings, fOlllllilg part hereof, is illustrated one form of embodiment of the invention, in which drawings similar reference characters designate corresponding parts, and in which: 1

Figure 1 is a perspective view, partly broken away, showing the conventional type of refrigerated cabinet with the application of the new evaporator plate thereto.

Figure 2 is a horizontal section of another conventional type of cabinet showing the application of the evaporator plate.

Figure 3 is an elevation, partly broken away, of the evaporator plate proper.

Figure 4 is a fragmentary section taken on line 4-4 of Figure 3, lookin in the direction indicated by the arrows.

Figure 5 is a, similar section, taken on line 5-5 of Figure 3, looking in the direction indicated by the arrows.

Figure 6 is a horizontal section, taken approximately on line 6--6 of Figure 3, looking downwardly.

Figure '7 is a similar view to Figure 6, taken approximately on line 'l1 of Figure 3.

Figure 8 is a perspective, partly broken away, showing the adaptation of the evaporator plate for use in a horizontal position.

Referring to the drawings, and with particular reference to Figure l, H designates a conventional type of refrigerated cabinet having a selfcontained compressor and condenser enclosed in an adjacent housing 12. The cabinet H is provided with covers l3 provided with knobs or handles M to open the same. As shown in Figure 1 there is enclosed in the cabinet ll an evaporator plate 15 having an intake passageway l6 fed through an opening 11, said plate being provided with baflles 18, more fully described hereinafter. The passageway It extends downwardly to supply the liquid refrigerant through the opening IB (see Fig. 5) in evaporator for flow upwardly, as shown by the arrows in Fig. 3. The evaporator plate 15 is provided with an exhaust or return opening ill by which the refrigerant may be drawn back to the compressor. It will be understood that'the necessary connections to and from the compressor and condenser are applied to the inlet and outlet portions of the plate 15, but since the system in general is well known, it is not deemed necessary to show the same or describe them in detail.

Wall brackets 20 are advantageously employed the lower portion of the opener:

for the dual purpose of holding the evaporator plate I in position and spacing it slightly from the floor of the cabinet ll, so that theefllciency of the evaporator plate is is not decreased by having to absorb heat which may pass through the floor of the cabinet H from the outside, and which would otherwise be absorbed by the plate I5 if the same were in direct contact with the floor of the, cabinet I I.

In Figure 2 isshown another form of conven-, tional type of refrigerated cabinetjin which the operating means are located at a point remote from the cabinet. The numeral 2| designates the conventional cabinet, provided with reenforcing rails 22 across the upper portion thereof, under which the plate l5 may be placed. A single plate is bent in such manner that it may substantially surround a number of compartments in the cabinet 2|. These compartments, designated as 23, may be of any desired shape,- but are herein shown as circular in the conventional manner of ice-cream cabinets, wherein cylindrical containers are usually used. Figures 3 to 7, inclusive, show the detailed construction of the evaporator plate. The plate II is formed of two sheets of metal, one sheet, 24, having a plain surface with the exception of the inlet passageway l6 formed therein, and the other I sheet 25, being formed with a plurality of spaced indentations 26, which are elongated horizontally to form ledges along their upper sides. The two sheets are joinedto one another by means of welds through the indentations 28 as shown at 21. It has been found advantageous to use a seam-weld rather than a spot-weld to hold the plates together. The edges of the plate are held together by seam-welds 28. The baflles it are formed by providing a seam-weld across the surface of the plate, as shown at 29, and also seaming the edges of the intake passage l6. At intermittent points the seam-welds 29 are broken to provide passageways 30 from the lower baflle l8, and passageways 3| from the upper baiiie l8.

Where a continuous evaporator plate, such as shown in Figure 2', is used, it is sometimes desirable to provide more than one intake passage l6 and outlet passage 19. Likewise, the spacing of the openings 30 and 3| in the baffles l8 may be regulated to suit the requirements of a particular installation.

With a plate as above described, the refrigerant is introduced through the opening l6 into the lower portion of the plate l6, during the active or on cycle of operation. The refrigerant then encounters the lower baiile l8 and must find its way through the passages 30 and subsequently through the passages ill in the upper baffle ll. This construction causes a violent turbulence in the refrigerant and has the effect of scouring the passageways between the indentations 26 so that any oil which may have become mixed with the refrigerant is carried back to the compressor. The oil, if any, is normally carried off from the evaporator plate in the form of a thin film on the gas bubbles which are formed when the refrigerant changes from a liquid to a gaseous state.

During the inactive or oil cycle of the operation, any oil which has not been returned to the compressor will settle on the ledges formed by the indentations 26 and will readily be picked up, upon starting of the on cycle of operation, and returned to the compressor rather than settling to the bottom of the plate l5.

By reason of the baflies l8 and the path which the refrigerant must follow, it is completely gasifled, so that it is delivered to the outlet I i as a dry rather than a wet gas, and eliminates the undesirable frosting of the return pipe which results when the refrigerant is allowed to vaporize too quickly.

In Figure 8 is shown another adaptation of the same type of evaporator plate. While capable of many other uses, it is particularly adapted for use in cafeterias and similar places as a "salad shelf, where dishes are prepared in advance and must be kept chilled. The plate l5 has a horizontal portion 32 having the lower baflle II in a horizontal plane and the upper baiiie 18 disposed in a vertical end wall 33. Even though the portion 32 be disposedin a horizontal position, the desired turbulence of the refrigerant is obtained by the arrangement of the baflles II and the indentations 26.

Having thus fully described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States, is:

1. In a refrigeration apparatus, an evaporator comprising two relatively thin metal sheets sealingly joined throughout their marginal edges and spacing means between said sheets within the area defined by said Joined edges, an inlet connection for supplying a volatile liquid refrigerant to the bottom portion of said evaporator between its opposite, ends, and an outlet connection for vapor adjacent the top edge of said evapprator, said spacing means consisting of spaced rows of uniformly, spacedly related indentations rovided on one of said sheets and disposed in face to face relation to the other sheet and forming between them passages for the circulation of the liquid refrigerant and vapor, said indentations being elongated and of greater length horizontally than their heighth and providing along their upper sides ledges on which the oil in the refrigerant is adapted to settle during the inoperative phase of each cycle of operation of the apparatus.

2. An evaporator as claimed in claim 1 wherein are provided in the evaporator between said inlet and outlet connections, bailles disposed parallel to the rows of indentations and each co-extensive in length to a plurality of said indentations.

3; An evaporator as claimed in claim 1 wherein are provided in the evaporator between said inlet and outlet connections spaced upper and lower baiiies each disposed parallel to the rows of indentations and co-extensive in length to a plurality of said indentations.

4. An evaporator as claimed in claim 1 wherein are provided in the evaporator between said inlet and outlet connections spaced upper, and lower baiiles disposed parallel to the rows of indentations and each being co-extensive in length to a plurality of said indentations, the lower baiiies being in spaced endwise relation and the upper baflles being spaced from the lateral edges of the evaporator, whereby the passages around the upper baflles are out of alinement with the passages between the lower bailies.

5. A refrigeration apparatus as claimed. in claim 1 wherein the indentations provided on one of said sheets terminate in curvilinear end walls.

6. In a refrigeration apparatus, sin-evaporator comprising two relatively thin metalsheets sealingly joined throughout their marginal edges, an inlet connection adjacent the lower edge of said evaporator for a volatile liquid refrigerant, an out.-

' let connection adjacent the opposite edge of said evaporator for vapor, spacing means between said nections, said spacing means consisting of hori- I zontally extending parallel rows of sections, the sections in each row being elongated horizontally to form ledges along their upper sides and spacedly related end to end to provide circulation passages for the liquid refrigerant between said rows of sections, and bailies disposed parallel to and between certain of said rows of sections.

7. In a refrigeration apparatus, an evaporator comprising two relatively thin metal sheets sealingly joined throughout their marginal edges, an inlet connection adjacent the lower edge of said evaporator intermediate the lateral edges thereof for a volatile liquid refrigerant, an outlet connection adjacent the upper edge of said evaporator intermediate the lateral edges thereof, and a baiile spaced irom and disposed parallel to the upper edge of said evaporator, the opposite ends of said baffle terminating in spaced relation to the lateral edges of said evaporator, one of said sheets being provided between said inlet connection and said baflie and between said outlet connection and said battle with inwardly extending indentations fixedly secured to the other sheet, said indentations being arranged in rows and elongated in directions parallel to said bafile and uniformly spaced in end to end relation, said indentations serving to space the sheets and form between them flow passages for and vapor.

the refrigerant 8. An evaporator as claimed in claim 7 wherein is provided a separate baflle between said inlet connection and said first mentioned baflle.

CHARLES C. HUBBELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 

